Liu S, Jiang J, Huang L, et al. - Researchers focused on the biological as well as clinical function of inducible nitric oxide synthase (iNOS) in intrahepatic cholangiocarcinoma (ICC). By means of real-time quantitative PCR and immunohistochemical staining, they determined iNOS expression in ICC and adjacent tissues. In ICC samples, a dramatic rise in the levels of iNOS mRNA and protein was noted. They also found a positive correlation of levels of iNOS mRNA and protein with complicated bile duct stone, differentiation, pathology T, pathology M, Wip1, MMP-2, and MMP-9. A significant correlation of iNOS expression with poor survival was also identified in ICC patients. In relation to low expression of iNOS, inhibition of proliferation yet promotion of apoptosis of ICC cells was reported. The possible therapeutic value of targeted inhibition of iNOS in ICC was highlighted in this study.